Why Nobody Cares About Audi G28

How to replace audi key an Audi G28 Engine Speed Sensor

In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is located on the outside of the transmission over the flywheel gear. It transmits a signal the ECU via a grey wire (T55/49) and then to the tachometer within the instrument cluster.

1. Engine Speed Sensor

The sensor is located at the edge of the transmission just above the flywheel ring gear G28 Engine Speed Sensor sends an electrical signal to ECU pin T55/49 through a grey wire. The ECU then utilizes this information to regulate the boost, fuel, and timig. It also sends an indication to the G5 Tachometer located in the instrument cluster.

The sensor serves as a reference point to connect with the G40 Camshaft Position Sensor. The ecu must be aware of when the crankshaft has reached TDC and also the location of the camshaft in order to activate the spark and injectors.

If this sensor fails when it fails, the ECU will display a P00160 error code. This indicates that the Crank Shaft is out of sync with the Intake Camshaft. It could also indicate an issue with the chain or a jumped chain link in the upper chain of timing. However, the error code won't appear on its own without additional information from other sensors (G4 and G40).

It is a little tricky to test as there are different pins on the connector and they all have different functions. The best way to do it is by measuring the resistance between the ECU and the sensor. If the sensor is operational, it should be reading approximately 1000 ohms. If you're having issues with this component, look for signs of oil or coolant in the connector bay.

2. Injectors

Yesterday, as i was accelerating off the highway paytoll at a high speed, i noticed a huge reduction in power. It was like the engine was running out of gas. Or my injectors were not firing. I took out the spark plugs this morning and found that 3 were soaked in gasoline, and the 4th was dry. I put tissue over each injector hole and when i start the engine with no sparks, the 3 that have gazoline pop right out. The 4th one remains shut. I tested the ground connection on ECU pins 14/55,30/55 and 48/55 I got zero Ohm. I'm assuming the issue is elsewhere.

I also tried to reset the PID with no success. The car will start when the G28 is unplugged and is running fine when it is connected however it has intermittent misfire issues at higher RPM. The coolant sensor (G62) even when unplugged, still shows temperatures of -49c. I also noticed that the oil gauge in my Area the cockpit shows 2 bar but the actual pressure is zero.

I'm not certain what to do, but i think i've pretty much ruled out everything else. But i'm worried that i might have missed something. If anyone has suggestions, please share them! TIA!

3. Fuel Pump

The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style transmitter is identical to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. It is easy to find the spare in a salvage shop or parts store. It is easy to test them - simply put your DMM into resistance mode and measure the distance between pins 1 and 2 (with the bump at the connector end facing up). They should be infinite ohms.

4. ECU

The ECU in our 20vt turbo (3B AAN ABY ADU) engines must know the position and speed the crankshaft to make decisions regarding fuel injector timing, etc. To accomplish this, it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you are experiencing issues with either one of these, the diagnostic scanner will show codes that could cause an engine shutdown.

A failing G28 sensor can cause an inaccurate gearbox speed counter and a gearbox which shifts more quickly than normal, and/or a misfire while in the gear. It is possible that the sensor is failing and needs to be replaced if you notice any of these signs. The good thing is that they are very affordable and readily available, especially in the case of the Bosch sensor, like ours. If you prefer, GM's version of this part is a good option.

5. Tachometer

A malfunctioning engine speed sensor could be the cause of many issues with your vehicle. It is a crucial part of the audi key replacement's transmission since it relays information to the ECU about how fast or slow the car's crankshaft is spinning. If this sensor fails, it will disrupt the performance of the transmission and the rest of the car's components.

The G5 engine speed sensor is located at the outside of the transmission above the flywheel ring gear. It sends a signal to the ECU at pin T55/49 via an uncolored wire. The ECU utilizes this signal to regulate the amount of fuel and boost, and also to timigrate. It also sends it to the G5 Tachometer in instrument cluster. You can test the sensor for failure by examining the continuity between it and the tachometer, between ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should see the resistance to be around 1000 ohms in these areas. This is a typical part across the audi q7 key 80, 100, 200, UrS and RS2 range from 1985 MC until the 1997 UrS AAN and 1995 RS2 ADU, so the best ones might be availble in wrecking yards.